Abstract ? Pathogen Detection and Quantification Core Maintenance of SPF status in macaque breeding colonies requires routine and accurate surveillance for the presence of infectious pathogens to maintain health of the animals and reduce risk of transmission. All viral screening assays for the TNPRC SPF breeding colony are currently being performed in the Pathogen Detection and Quantification Core (PDQC) at the TNPRC. Confirmatory testing for non-negative screening results is performed at the Pathogen Assay Laboratory (PAL) at the California National Primate Research Center (CNPRC), Charles River (CR), and National B Virus Resource Laboratory (NBVRL). This two-tiered testing algorithm (screening and confirmatory testing) between the PDQC and outside laboratories and experts has improved both accuracy and efficiency in the current diagnostics surveillance program for maintaining the SPF colonies over the previous 5-year period of this base grant. Transfer of the SPF surveillance program to the PDQC also has reduced; a) diagnostic testing costs, b) shipping of samples and, c) turn-around time for reporting test results. In addition, expanded diagnostics surveillance or screening to detect additional infectious agents (viral and non-viral) has been introduced based on emerging needs and adaptability to the PDQC testing platforms. It is recognized that accurate testing methods to especially avoid false negative results is essential. All breeding colony animals are tested at a minimum of twice a year during semi-annual health assessments in an effort to detect any outbreaks before they spread to large numbers of animals. Data are provided in the Research Strategy to support the need for continued surveillance at the proposed frequency and capacity. Additionally, leadership in the Division of Veterinary Medicine and PDQC personnel have contributed significantly to the recent publication produced by the Nonhuman Primate Research Consortium (NHPRC), and Breeding Colony Management Consortium (BCMC) on current pathogen testing methods and management in SPF macaque colonies.